By Dr. Ananya Mandal, MD
Human Growth Hormone (hGH) has long been used among athletes and body builders for stronger and a more muscular bodies over the past four decades. However it is only now that Sydney-based researchers have published a study that shows that hGH offers no such benefits.
hGH is a hormone that the body normally produces and it helps in the development of muscles and organs. The study results show that hGH gives a 4% improvement in the stamina for running but had not effect on endurance, strength and fitness. One of the study volunteers also developed a condition called gynaecomastia or abnormal development of breasts in a male as a side effect to hGH. Fluid retention, bloating, pain in the joints were some other side effects experienced by the volunteers.
Professor Ken Ho from Sydney's Garvin Institute of Medical Research was the lead author of this study. He expressed his delight and surprise at the results. “The improvement in performance was observed in a selective aspect of physical function - that of sprint capacity…We did not find any effect on endurance, strength and power, which are areas of physical performance which most people expected growth hormone to work on,” he said. This study was funded by the World Anti-Doping Agency (WADA).
The study spanned over eight weeks and included 96 healthy, recreationally trained athletes with an average age of 27. The 63 male volunteers were divided into four groups with each getting;
- 2 milligrams per day of hGH
- 250 milligrams per week of testosterone
- Both hGH and testosterone
- Placebo injections.
The 33 female participants received either growth hormone or placebo injections. None of the participants or examiners knew who got what. All the participants then underwent physical and laboratory examinations.
At the end of the study results showed that hGH improved sprint capacity in men and women by an average of 3.9% over the placebo group. According to Dr. Ho this would cut down 0.4 of a second from a 10-second time in the 100-meter dash. Men who received both growth hormone and testosterone had an 8.3% average increase in sprint capacity, the study found. hGH also reduced body fat and made muscles leaner. The study was published in Annals of Internal Medicine this Monday.